Carboxylic acid glycuronides, glycosamides and glycosides of quinolones, penicillins, analogs, and uses thereof

ABSTRACT

Disclosed are caboxylic acid glycuronides, glycosamides and glycosides of quinolones, penicillins and analogs thereof to treat conditions and diseases such as bacterial infections.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to carboxylic acid glycosamides andglycosides of quinolones and penicillins and analogs thereof.

2. Related Art

Ofloxacin is a broad spectrum antibiotic of the quinolone class. SeeU.S. Pat. No. 4,382,892, which discloses ofloxacin and analogs thereof.Other drugs which are in the class of quinolones include ciprofloxacin,enoxacin, gatifloxacin, levofloxacin, lomefloxacin, moxifloxacin,norfloxacin, ofloxacin, pefloxacin, sparfloxacin, nalidixic acid andtrovafloxacin. The penicillin group of antibiotics also contain acarboxyl group. In particular, amphicillin, carbenicillin andpenicillin-G belong to the beta lactan antibiotics containing acarboxylic acid group.

SUMMARY OF THE INVENTION

The present invention relates to a pro-drug approach to quinolone andbeta lactam group of drugs that provides better bioavailability. Thepro-drug is in the form of carboxylic acid glycuronides, glycosamidesand glycosides of compounds belonging to the drug class often referredto as quinolones. Similar pro-drug approach can be extended to betalactam group of antibiotics utilizing the carboxylic acid group. Thecarboxy group may be amidated with a protected amino sugar to give aglycosamide. Alternatively, the carboxy group may be esterified with aprotected glycuronic acid to give a glycuronic acid ester or with aprotected glycose to give a carboxylic acid glycose ester. Theprotecting groups are then partially or completely removed. Whenadministered, the pro-drug targets the pathogen, especially bacteria andfungi. The cell surface of the bacterial walls exhibit enhancedglycosamine expression than the humans. Reference: Bacterialpathogenesis, A molecular approach by Abigai A. Salyers and Dixie D.Whitt, ASM press, Washington D.C. (1994). Thus, the compounds of theinvention may have the advantage of targeting the pathogen moreeffectively.

The amidase and glycosidase enzymes present within the pathogen willliberate the drug causing the cell specific damage that is intended.Also when administered, glycosidase, amidase and esterase enzymes in thebiological medium of human body cleave the ester/amide bonds, thusliberating the free drug. Thus, the free drug is bioavailable in acontrolled fashion as determined by the rate ofde-amidation/de-esterification. The compounds of the invention can beused for the treatment of any condition treatable by quinolones andpenicillins including bacterial infections.

The present invention relates in particular to compounds of the Formula(I):A-R′  (I)wherein A is the residue of a quinolone, penicillin or analog thereofand R′ represents the residue of glycuronic acid, glycosamine orglycoside.

The present invention also relates to compounds having Formula (II):

wherein X represents a halogen atom, R represents a hydrogen atom or analkyl group having from 1 to 6 carbon atoms, R′ represents the residueof glycuronic acid, glycosamine or glycoside, and Z represents amono-substituted amino group, a di-substituted amino group, or acyclic-substituted amino group which may contain another hetero-atom,and the substituted amino group may be further substituted with one ormore substituents selected from the group consisting of hydroxyl, alkylhaving from 1 to 6 carbon atoms, amino, hydroxyalkyl having from 1 to 6carbon atoms, monoalkylamino and dialkylamino having from 1 to 6 carbonatoms in each alkyl moiety, and pharmaceutically acceptable saltsthereof. Preferably, R′ is a straight or branched chain glycosidicresidue containing 1-20 glycosidic units per residue, or a glucuronicacid or glucosamine residue.

The invention also relates to a method for the treatment or ameliorationof any condition treatable with quinolones, penicillins and analogsthereof, comprising administering to an animal in need thereof, aneffective amount of a compound of the invention, or a pharmaceuticallyacceptable salt thereof.

The invention also relates to a method of preparing a compound ofFormula (I) which comprises condensing a protected saccharide,aminosaccharide or glycuronic acid with a quinolone, penicillin oranalog thereof, wherein said quinolone, penicillin or analog thereofthat has a carboxy group, in solvent, and isolating the protectedcarboxylic acid glycuronide, glycosamide or glycoside ester. Theprotecting groups may then be partially or completely removed.

DETAILED DESCRIPTION OF THE INVENTION

Where the derivative is a glycose ester, then it is preferred that itcontain 1-20 glycosidic units.

It is preferred that compounds of the present invention have less than10 and, more preferably, 3 or less glycosidic units. Specific examplesare those containing 1 or 2 glycosidic units in the glycoside residue,such as glucose and sucrose, with one being most preferred.

By glycosidic units are meant glycopyranosyl or glycofuranosyl, as wellas their sulfates and/or deoxy derivatives. The configuration of eachunit may be D or L, although D is generally preferred. The residues maybe homopolymers, random or alternating polymers, or block copolymers ofthese monomers.

The glycosidic units have free hydroxy groups, or the hydroxy groups maybe acylated, e.g. with a group R₄—(C═O)—, wherein R₄ is hydrogen, C₁₋₆alkyl, C₆₋₁₀ substituted or unsubstituted aryl or C₇₋₁₆ aralkyl.Preferably, the acyl groups are acetyl or propionyl. Other preferred R₄groups are phenyl, nitrophenyl, halophenyl, lower alkyl substitutedphenyl, lower alkoxy substituted phenyl and the like or benzyl, loweralkoxy substituted benzyl and the like.

The glycopyranose or glycofuranose ring or amino derivative thereof maybe fully or partially acylated or completely deacylated. The completelyor partially acylated glycoside is useful as a defined intermediate forthe synthesis of the deacylated material. Useful protecting groupsinclude, but are not limited to, acetyl, benzoyl, nicotinoyl, benzyl,methyl and phenyl.

Among the possible glycopyranosyl structures are glucose, mannose,galactose, gulose, allose, altrose, idose, or talose. Among thefuranosyl structures, the preferred ones are derived from fructose,ribose, arabinose or xylose. Among preferred diglycosides are sucrose,cellobiose, maltose, lactose, trehalose, gentiobiose, and melibiose.Among the triglycosides, the preferred ones may be raffinose orgentianose.

Where there are linked glycosidic units, i.e., there is a di orpolyglycosidic residue, the individual glycosidic rings may be bonded by1-1, 1-2, 1-3, 1-4, 1-5 or 1-6 bonds, most preferably 1-2, 1-4 and 1-6.The linkages between individual glycosidic rings may be α or β.

Aminosaccharides include glucosamine (e.g. the amine is either in the 1-or 2-position), mannosamine, and galactosamine.

Glycuronic acids include hyaluronic acid, glucuronic and galacturonicacids.

In Formula (II), mono-substituted amino group include monoethylamino ormonomethylamino, and examples of the di-substituted amino group includediethylamino or dimethylamino. The expression “cyclic-substituted aminogroup” refers to a 4- to 7-membered ring and examples thereof includeazetidinyl, pyrrolidinyl, piperidinyl, morpholinyl, piperazinyl andhomopiperazinyl (hexahydro-1H-1,4-diazepin-1-yl). More particularly, thesubstituent Z means, for example, 4-methyl-1-piperazinyl, 1-piperazinyl,1-pyrrolidinyl, 3-hydroxy-1-pyrrolidinyl, 1-piperidinyl,4-hydroxy-1-piperidinyl, 3-hydroxy-1-piperidinyl, 4-morpholinyl,4-(2-hydroxyethyl)piperazinyl, 3,5-dimethyl-1-piperazinyl,4-dimethylamino-1-piperidinyl, homopiperazinyl, 1-pyrazolidinyl,2-methyl-1-pyrazolidinyl, N-(2-hydroxyethyl)amino,N-(2-hydroxyethyl)-N-methylamino, hydrazyl, and methylhydrazyl. See U.S.Pat. No. 4,382,892. A preferred compound of Formula (II) is ofloxacin.

Other quinolones and penicillins that may be prepared in the form ofcarboxylic acid glycuronides, glycosamides and glycoside esters include,but are not limited to ciprofloxacin, enoxacin, gatifloxacin,levofloxacin, lomefloxacin, moxifloxacin, norfloxacin, ofloxacin,pefloxacin, sparfloxacin, nalidixic acid, trovafloxacin, penicillin,cephalexin, carbenicillin indanyl and cephradine. Where the drug is anamide, the corresponding carboxylic acid may be used.

The compound of this invention can form an acid addition salt with aninorganic or organic acid such as hydrochloric acid, sulfuric acid,methanesulfonic acid and the like.

Especially preferred compounds include the glucose and glucuronic estersof ofloxacin as well as the glucosamide of ofloxacin and thepharmaceutically acceptable salts thereof.

Esters of the compounds of the invention include esters of any freehydroxy groups on the glycose, glycosamine and glycuronide. Such estersinclude the group R₄—C═O)—, wherein R₄ is as defined above. Preferablysuch esters are acetate groups which also serve as a protecting group inthe condensation reaction.

The carboxylic acid glucuronides may be obtained by condensation of ablocked sugar epoxide with a quinolone (e.g. ofloxacin), penicillin oranalog thereof according to the methods disclosed in U.S. Pat. No.5,633,357. The glycosamides may be prepared by condensation of aprotected glycosamine with a quinolone (e.g. ofloxacin), penicillin oranalog thereof in the presence of a condensation agent such asdicyclohexyl carbodiimide, DMT-MM or similar agent. The glycose may beprotected in 2,3,4,6-positions, e.g. as an acetate, and the anomericposition may be activated as a halide or chloroimidate and then reactedwith the carboxylic acid to form the glycoside. The protecting groupsmay be removed, e.g. by selective deacetylation by using the basichydroxy resins.

The compounds of the present invention are particularly useful fortreatment of infections caused by most facultative gram-negative rods,and have fair activity against staphylococci, and variable to pooractivity against streptococci. They are particularly active against P.aeruginosa. Particular diseases and conditions that may be treated withthe compounds of the invention include urinary tract infections,infectious diarrhea, systemic gram negative infections, bacterialgastroenteritis, enteric fever, osteomyelitis, gonoccocal infections,amebiosis, bronchitis, complicated skin and soft tissue infections,pneumonia sinusitis, acute maxillary, Streptococcus pneumoniaeinfection, urinary tract infection and chronic otitis extema in adults.

Particularly preferred routes of administration of the compounds of thepresent invention are per os, such as elixirs, tablets and capsules, asexemplified below, and by i.v. administration.

More generally, the compounds of the present invention can beadministered in any appropriate pharmaceutically acceptable carrier fororal administration since the compounds are biologically active uponoral administration. The compounds of the invention may also beadministered in any appropriate pharmaceutical carrier for parenteral,intramuscular, transdermal, intranasal, buccal or inhalationadministration. They can be administered by any means that treat orameliorate the conditions and diseases described herein.

The dosage administered will depend on the age, health and weight of therecipient, kind of concurrent treatment, if any, frequency of treatmentand the nature of the effect desired. An exemplary systemic daily dosageis about 0.1 mg to about 500 mg. Normally, from about 1.0 mg to 100 mgdaily of the compounds, in one or more dosages per day, is effective toobtain the desired results. One of ordinary skill in the art candetermine the optimal dosages and concentrations of active compoundswith only routine experimentation.

The compounds can be employed in dosage forms such as tablets andcapsules for oral administration. Such dosage forms may comprise wellknown pharmaceutically acceptable carriers and excipients. In apreferred embodiment, the dosage forms comprise cyclodextran and/orother saccharides and/or sugar alcohols. The compounds may also beformulated in a sterile liquid for formulations such as solutions (e.g.in saline) or suspensions for parenteral use. A lipid vehicle can beused in parenteral administration. The compounds could also beadministered via topical patches, ointments, gels or other transdermalapplications. In such compositions, the active ingredient willordinarily be present in an amount of at least 0.001% by weight based onthe total weight of the composition, and not more than 50% by weight. Aninert pharmaceutically acceptable carrier is preferable such as 95%ethanol, vegetable oils, propylene glycols, saline buffers, sesame oil,etc. Remington's Pharmaceutical Sciences, 18^(th) Edition, Gennaro etal. (eds.), 1990, exemplifies methods of preparing pharmaceuticalcompositions.

The compounds may also be employed in fast dissolving dosage forms, asdescribed in U.S. Pat. No. 6,316,027, comprising the compounds of theinvention, water, gelatin and other ingredients.

Topical formulations for transdermal, intranasal or inhalationadministration may be prepared according to methods well known in theart. For topical administration, the compounds may be applied in any ofthe conventional pharmaceutical forms. For example, the compounds may beadministered as part of a cream, lotion, aerosol, ointment, powder,drops or transdermal patch. Ointments and creams may, for example, beformulated with an aqueous or oily base with the addition of suitablethickening and/or gelling agents. Such bases may include water and/or anoil such as liquid paraffin or a vegetable oil such as peanut oil orcastor oil. Thickening agents which may be used include soft paraffin,aluminum stearate, cetostearyl alcohol, polyethylene glycols, wool-fat,hydrogenated lanolin, beeswax and the like.

Lotions may be formulated with an aqueous or oily base and will ingeneral also include one or more of a stabilizing agent, thickeningagent, dispersing agent, suspending agent, thickening agent, coloringagent, perfume and the like.

Powders may comprise any suitable powder base including talc, lactose,starch and the like. Drops may comprise an aqueous or non-aqueous basetogether with one or more dispersing agents, suspending agents,solubilizing agents and the like.

The compositions may further comprise one or more preservativesincluding bacteriostatic agents including methyl hydroxybenzoate, propylhydroxybenzoate, chlorocresol, benzalkonium chloride and the like.

The topical compositions comprise from about 0.0001% to 5% by weight,preferably, 0.001 to 0.5% by weight, more preferably, 0.01 to 0.25% byweight of the active compounds.

The compounds of the invention are substantially pure. The phrase“substantially pure” encompasses compounds created by chemical synthesisand/or compounds substantially free of chemicals which may accompany thecompounds in the natural state, as evidenced by thin layerchromatography (TLC) or high performance liquid chromatography (HPLC).

Animals which may be treated according to the methods of the presentinvention include all animals which may benefit therefrom. Included insuch animals are humans, although the invention is not intended to be solimited.

Having now generally described this invention, the same will beunderstood by reference to the following examples which are providedherein for purposes of illustration only and are not intended to belimiting unless otherwise specified.

EXAMPLE 1 Synthesis of N-(p-methoxybenzylidene)-D-glucosamine

D-glucosamine hydrochloride (215 g; 1 mole) was dissolved in sodiumhydroxide solution (1N; 1 liter) and p-anisaldehyde (122 mL) was added.The solid product obtained was filtered off and dried. The product (250g) had a melting point of 165° C. in accordance with the literature.

Synthesis ofN-(p-methoxy-benzylidene)-1,3,4,6-tetra-O-acetyl-D-glucosamine

The p-anisylidene derivative obtained above (250 g) was dissolved inpyridine (1.25 mL) and acetic anhydride (750 mL) was added slowly atroom temperature. The mixture was stirred for 12 hours at roomtemperature and the clear solution was poured into crushed ice/watermixture (5 liters) and filtered. The precipitate was filtered off andcrystallized from methanol (270 g). The product had a melting point of180-1° C. in accordance with the literature.

Synthesis of 1,3,4,6-tetra-O-acetyl-D-glucosamine Hydrochloride

To a boiling solution of tetra-O-acetyl-p-anisylidene derivative (150 g)obtained as above in acetone (750 mL) was added hydrochloric acid (SN;62.5 mL). After stirring the mixture mechanically for 15 minutes, theproduct was isolated by cooling and adding ether (100 mL) to facilitatecomplete precipitation. The precipitate was filtered and washed oncewith ether and dried (100 g; m.p.=230° C.).

Synthesis of 6-(2′)-glucosylamino(+)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyyrido[1,2,3,-de]-1,4-benzoxazine-6-carboxamide (Glucosamido-Ofloxacin)

Glucosamine hydrochloride (950 mg; 4.4 mMol) was dissolved in water (10mL) and sodium bicarbonate (380 mg; 4.4 mMol) was added. The solutionstirred for few minutes and lyophilized. Dried glucosamine was suspendedin dimethylformamide (20 mL) and ofloxacin (1.45 g; 4 mMol) was added atroom temperature. Dicyclohexyl carbodiimide (900 mg; 4.4 mMol) wasadded. The resulting solution was stirred for 16 hours at roomtemperature. The precipitate was filtered off and the dimethylformamidesoluble portion was lyophilized and chromatographed usingmethanol-dichloromethane mixtures over silica gel. The desired productwas obtained as a gummy solid (850 mg).

Proton NMR spectrum in D₂O: δ (1.6; broad singlet; 3-H; methyl); δ (2;singlet; 3-H; N-methyl); δ (2.6; broad singlet; 4-H; N—CH₂); δ (3.4;broad multiplet; 4-H; N—CH₂); δ (4.0-4.8; complex multiplet; 9-H;glucosyl-H and C—H of ofloxacin); δ (5.3; doublet; 1-H; glucosyl-H) andδ (8.5; singlet; Aromatic-H; 1-H).

Synthesis of 6-[1′,3′,4′,6′-tetra-O-acetyl-glucosyl-2′-amino(+)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyyrido[1,2,3,-de]-1,4-benzoxazine-6-carboxamide(tetra-O-acetyl-Glucosamido-Ofloxacin)

1,3,4,6-tetra-O-acetyl-glucosylamine hydrochloride (1.8 g; 4.4 mMol)suspended in dimethylformamide was added sodium bicarbonate (380 mg) andstirred at room temperature for an hour to dissolution. Ofloxacin (1,45g; 4.4 mMol) was added followed by dicyclohexylcarbodiimide (900 mg; 4.4mMol). The solution was stirred for 16 hours at room temperature. Theprecipitate was filtered and discarded. The clear solution waslyophilized and crystallized from ether (1.2 g).

Proton NMR spectrum in CDCl₃: δ (1.65; broad singlet; 3-H; methyl); δ{2-2.6; complex overlap of singlets; 19-H; N-methyl, N—CH₂ (4H) and(12H)acetyl}; δ (3.4; broad multiplet; 4-H; N—CH₂); δ (4.0-5.2; complexmultiplets; 10-H; glucosyl-H and C—H of ofloxacin); and δ (8.5; singlet;Aromatic-H; 1-H) in accordance with the structure.

From the foregoing description, one skilled in the art can easilyascertain the essential characteristics of this invention, and withoutdeparting from the spirit and scope thereof, can make various changesand modifications of the invention to adapt it to various usages andconditions without undue experimentation. All patents, patentapplications and publications cited herein are incorporated by referencein their entirety.

1. A compound which is a carboxylic acid glycuronide, glycosamide orglycoside ester of a quinolone, penicillin or analog thereof, or saltthereof.
 2. The compound of claim 1, wherein the compound has theFormula (II):

wherein X is a halogen atom, R is a hydrogen atom or an alkyl grouphaving from 1 to 6 carbon atoms, R′ represents the residue of aglycuronic acid, glycosamine or glycoside and Z represents (1) amono-alkylamino or di-alkylamino group or (2) a cycloamino groupselected from the group consisting of azetidinyl, pyrrolidinyl,piperdinyl, morpholinyl, piperidinyl, homopiperazinyl, thiamorpholinyland pyrazolidinyl, each of which amino groups may be substituted with ahydroxyl group, an alkyl group having 1 to 6 carbon atoms, an aminogroup, a hydroxyalkyl group having 1 to 6 carbon atoms or a mono- ordi-alkylamino group having 1 to 6 carbon atoms in each alkyl group.
 3. Acompound as in claim 2, wherein Z represents a mono-substituted aminogroup selected from monoethylamino and monomethylamino, a di-substitutedamino group selected from diethylamino and dimethylamino, and acyclic-substituted amino group comprising a 4- to 7-membered ringselected from azetidinyl, pyrrolidinyl, piperidinyl, morpholinyl,piperazinyl and homopiperazinyl.
 4. A compound as in claim 2, wherein Ris methyl and Z is 4-methyl-1-piperazinyl.
 5. A compound as in claim 2,wherein R is methyl and Z is 4-hydroxy-1-piperazinyl.
 6. A compound asin claim 2, wherein R is methyl and Z is 3-hydroxy-1-pyrrolidinyl.
 7. Acompound as in claim 2, wherein R is methyl and Z is homopiperazinyl. 8.The compound of claim 1 which is glucosamido-ofloxacin.
 9. The compoundof claim 1, which is a glycose ester containing 1-20 glycose units. 10.The compound of claim 1, wherein said compound is a monoglycose.
 11. Thecompound of claim 6, wherein said glycose unit is a glucose.
 12. Thecompound of claim 1, wherein said compound is a glucuronic acid ester.13. A pharmaceutical composition comprising the compound of claim 1 anda pharmaceutically acceptable carrier.
 14. A method for the treatment oramelioration of a pathogenic infection in an animal, comprisingadministering to an animal in need thereof an effective amount of thecompound of claim
 1. 15. The method of claim 14, wherein said compoundis administered as part of a pharmaceutical composition comprising apharmaceutically acceptable carrier therefor.
 16. The method of claim14, wherein said animal is a human.
 17. The method of claims 16, whereinsaid compound is glucosamido-ofloxacin.
 18. The method of claim 14,wherein said pathogenic infection is a bacterial infection.
 19. Themethod of claim 14, wherein said pathogenic infection is a fungalinfection.